Introduction: Cohen-Mansfield Agitation Inventory (CMAI) is frequently used in patients with dementia for the assessment of agitation severity. This instrument is especially used in research investigating the severity of behavioral symptoms and their treatment responses. In this study, psychometric properties of the Turkish version of CMAI were investigated in patients with dementia (n=52). Materials and Method: CMAI-Turkish version was applied by face-to-face interview to the caregivers of dementia patients who were admitted to a geriatric psychiatry outpatient clinic. For validity, the correlations between CMAI total scores and Neuropsychiatry Inventory (NPI) total and subscale scores were evaluated. For internal consistency, Cronbach alpha value of the items was calculated. Results: CMAI scores were significantly correlated with NPI scores and Cronbach alpha value of the scale was high (0.89). Conclusion: Turkish version of CMAI is a valid and reliable tool for the assessment of the frequency and severity of agitation behavior. Further studies might evaluate inter-rater reliability of the scale in inpatients with dementia.